Mostro Mobile is a free, open-source client for the Mostro peer-to-peer exchange platform, made for people who want to trade Bitcoin over the Lightning Network while keeping their trade communications private. It is built with Dart and Flutter, targets Android and iOS, and also offers a Windows build or installer for desktop users. Because trades run over Nostr relays, there is no central authority controlling the process.
The project's status matters before you install anything: the app is deprecated, its repository is archived, and v1.5.0 is the last release. It receives no more updates or fixes, so treat it as a finished version rather than an actively maintained product. The rest of this page explains what it does, how its privacy design works, how to install it safely and how it compares with other Nostr-based tools.
What Is Mostro Mobile and Who Is It For?
Mostro Mobile is the mobile front end of the Mostro peer-to-peer exchange. Instead of depending on a company to match buyers and sellers, the platform lets users post and accept orders over Nostr relays, and this app is the handheld client for doing that. It is aimed at people who already understand Bitcoin and want a private way to arrange Lightning-based trades.
The typical reader is a Bitcoin user who values privacy, dislikes relying on centralized intermediaries and is comfortable managing their own keys. Developers and students of decentralized systems also find it useful as a working example of Nostr, Lightning and per-trade key management combined in one app.
It is less suited to beginners who have never used a Bitcoin wallet. Because the app puts key management and payment steps in the user's hands, a basic grasp of seed phrases and invoices makes the experience much smoother and reduces the chance of mistakes.
How a Peer-to-Peer Trade Works Over Nostr and Lightning
A Nostr client talks to a set of relays, which are simple servers that store and forward signed messages. Mostro Mobile uses this network to publish orders and pass messages between the two sides of a trade. Because the relays do not hold accounts, the system works without a central database of users.
A typical trade begins with an order listed in the order book. One party posts an offer, the other accepts it, and the two sides exchange messages to agree on the next steps. The Lightning Network then handles the payment leg through an invoice, which the paying side checks before sending funds.
Because each trade can use its own key, the messages from one deal are not automatically tied to the messages of another. This separation is one of the design choices that distinguishes the app from general-purpose chat clients built on the same protocol.
Key Terms Explained: Relays, Gift Wrapping and Seed Phrases
Several terms appear throughout the app, and knowing them makes the rest of this page easier to follow. A relay is a server that accepts and forwards Nostr events, and a client can connect to more than one relay at a time. Relays see the traffic they carry, which is why encryption layers matter.
Gift wrapping, defined in NIP-59, places a message inside another encrypted envelope so that the content and the sender are harder to link to an identity. A seed phrase is a list of words, defined by BIP-39, from which a wallet or app derives its private keys. Anyone who learns the seed phrase can recreate those keys, so it must be stored offline and never shared.
A Lightning invoice is a payment request that includes an amount and a destination. Reading it carefully before paying is one of the simplest ways to avoid errors, because a Lightning payment is generally difficult to reverse once it has been sent.
Key features
Private trade messages
A separate key for each trade
Lightning payments and invoices
Live order book and trade chat
Interface in three languages
Card-based layout
Hardware-backed key storage
Android, iOS and Windows builds
No central operator
Supported coins
Trades on Mostro Mobile are built around Bitcoin (BTC) and the Lightning Network, which handles the payment side of each deal. Nostr serves as the network that carries orders and messages between users. Plan your activity around Bitcoin, since that is the asset the platform is designed to handle.
How to install Mostro Mobile on Windows
- 1
Get the Windows build
Go to the official website or to the project's GitHub Releases page at github.com/MostroP2P/mobile. Download only from the official website or that repository, and choose the v1.5.0 release, which is the last one published. Avoid files shared through forums, chat groups or mirror sites.
- 2
Verify the file
Calculate the SHA-256 checksum of the downloaded file and compare it with the value published with the release. If a signature is provided, check it as well. Do not run an installer whose checksum does not match the published value.
- 3
Run the installer
Open the downloaded file and follow the setup prompts. Choose an install folder you control and keep the default settings unless you have a specific reason to change them. Close the installer once it reports that setup is complete.
-
Set up your keys
On first launch, follow the in-app prompts to create or restore your keys. Write any seed phrase on paper and store it somewhere offline, such as a locked drawer. Confirm that your backup works before you rely on the app for any trade.
How to use Mostro Mobile
Mostro Mobile follows a simple pattern: set up your keys, browse orders, and complete a trade through Lightning payments and in-app messages. Work through the steps below the first time, preferably with a small amount, so you learn the flow before committing more.
- Open the app and choose your preferred language among English, Spanish and Italian.
- Review your key setup and confirm that your seed phrase backup is stored offline.
- Browse the order book to see live offers and filter them by what you are looking for.
- Create a new order or accept an existing one, reading all terms before you confirm.
- Use the built-in chat to coordinate with your counterpart and confirm the details of the trade.
- When a Lightning invoice appears, check that the amount and destination match what was agreed before you pay.
- After the trade completes, note the outcome and keep your records in case you need to review them later.
Take your time at each step. Trades are easier to manage when you keep each order's details in one place and avoid switching between several conversations at once.
Pros & cons
- Trade messages use NIP-59 gift wrapping for an extra privacy layer
- A separate key for each trade, derived from a seed with BIP-32 and BIP-39
- Free to use and released under the MIT license, so the code can be inspected and reused
- Lightning Network support for Bitcoin payments and invoices
- Interface available in English, Spanish and Italian
- Decentralized design with no central authority over orders
- The project is deprecated and its repository is archived, so v1.5.0 receives no updates or security fixes
- It was built primarily as a mobile app, so the Windows build is a secondary option
- Requires familiarity with Bitcoin Lightning and Nostr concepts before trades feel comfortable
- Its documented focus is Bitcoin, so it is not a tool for other coins
- Keeping seed phrases and private keys safe is entirely the user's responsibility
Is Mostro Mobile safe?
Mostro Mobile handles keys and Lightning payments, so safety matters more than usual. The project is deprecated and its repository is archived, which means v1.5.0 will not receive security patches. Each new vulnerability that is found in the future will stay unfixed, so your risk grows over time.
Download only from the official website or the project's GitHub repository. Verify the SHA-256 checksum or signature before running the installer. Never enter your seed phrase on a third-party website, in a chat or in an email, and do not accept any tool that asks for it. Check the latest version information on the official website before installing, and keep backups of your keys offline.
- Official source only. Download from github.com/MostroP2P/mobile. Ignore ads and lookalike domains.
- Check the SHA-256. Compare the installer hash with the value the developer publishes before running it.
- Never share your seed phrase. No developer, support agent or website — including CryptApps — will ever ask for it.
Alternatives
Mostro Mobile sits in a narrow niche: it is a trading client for peer-to-peer Bitcoin orders over Nostr and Lightning. Nostrid is a broader multi-platform Nostr client with Windows binaries, so it suits general social browsing rather than trade flows. Keychat combines chat with Bitcoin and ecash support, which makes it a messaging-first choice.
Bro App focuses on paying bills with Bitcoin through a peer-to-peer protocol built on Nostr and Lightning, so its goal is everyday payments rather than order matching. Vega is a desktop Nostr client, useful if you want a Windows-first way to read and post on Nostr without the trading layer. Choose based on whether you need trading, chat, bill payments or general Nostr access.
Specifications
- Price
- Free
- Type
- Open source
- License
- MIT
- Latest version
- v1.5.0
- Last update
- 22 Oct 2026
- Windows support
- Yes (Windows build or installer)
- Source code
- github.com/MostroP2P/mobile
Frequently asked questions
No, the project is deprecated and its repository is archived. v1.5.0 is the last release, and it receives no further updates or fixes. Bugs and security issues found after the archive will not be patched, so weigh that carefully before using the app with real funds.
It can be, if you get the file from the official GitHub repository or website and verify its SHA-256 checksum or signature. Because the app is archived, it will not receive security fixes, so the risk grows over time. Read the safety section before installing anything.
Yes, a Windows build or installer is available alongside the Android and iOS versions. The app was built primarily for mobile devices, so judge the desktop build on its own terms and confirm that your workflow fits before relying on it.
Yes, the app itself is free and released under the MIT license. The software costs nothing to download, but any Bitcoin amounts you trade are separate and depend entirely on the deals you make with other users.
NIP-59 is a Nostr specification for gift wrapping, a method that places an encrypted message inside another envelope. This makes the content and sender harder to link on public relays. Mostro Mobile uses this approach for its trade communications.
The project focuses on Bitcoin (BTC) and the Lightning Network for payments, with Nostr carrying orders and messages. Plan your trades around Bitcoin rather than other tokens, since that is the asset the platform is designed to handle.
A Lightning invoice is a payment request that states an amount and a destination. Before paying, check that the amount and recipient match the terms you agreed to in the chat. Lightning payments are generally difficult to reverse, so this check matters.
Verdict
Mostro Mobile is a thoughtful reference for private, per-trade key management and Bitcoin Lightning trading over Nostr, but it is now archived and no longer receives fixes. It fits readers who want to study the design, understand how peer-to-peer trades fit with Nostr privacy, or test the flow with small amounts. For regular trading with meaningful funds, look for actively maintained alternatives and treat this version as a historical release.